1. The Field of the Invention
The present invention relates generally to devices to replace knots and more specifically to devices to replace surgical knots tied in open, arthroscopic, and endoscopic procedures.
2. The Relevant Technology
Numerous devices have been developed to eliminate the need to tie knots as a way of securing a line. The devices that accomplish the same function as a knot, which is in part to secure a line to retain tension in a portion of the line, are typically referred to as line locks.
Line locks generally operate in one of two ways. Some line locks are manually actuated to secure one or more lines so that tension is maintained in a portion of the line(s). Once actuated, the line lock resists sliding along the line(s) either toward or away from the tensioned portion of the line. Other line locks are continuously adjustable in one direction so that tension is increased in the portion of the line upon which the line lock is advanced. The continuously adjustable line locks resist movement away from the tensioned portion of the line, but can be further advanced toward the tensioned portion of the line with an appropriately applied force.
The portion of a line that is put under tension, typically to secure some object, is commonly referred to as the standing end. The portion of the line that extends toward the line handler is commonly referred to as the working end. A knot in a line, or a line lock attached to a line, is the demarcation between the standing end and the working end.
Continuously adjustable line locks offer several advantages. They are passive locking devices, meaning that no other operation is required to secure the line lock once it is moved along the line to its desired position. Furthermore, these line locks can be used to continuously increase the tension in the standing end until it reaches a desired level of tension.
The advantages of line locks over tied knots are very attractive in many varied applications, including the use of surgical sutures. However, the line locks developed to date have many deficiencies when considered for surgical suture applications. For example, many known line locks for surgical applications are somewhat small, and as a result, they have small passageways that are positioned quite close to each other. This makes threading the suture through the line lock somewhat difficult. Furthermore, the user must often take special care to thread the suture through the line lock in the proper pattern. Use of an improper threading pattern may cause the line lock to operate improperly, and possibly, to fail to retain the tissue it is applied to.